Examine source code of kill-tab

{
  "manifest_version": 2,
  "name": "kill-tab",
  "version": "1.1",
  "description": "kills youtube tab when video ends",
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/watch?v=*"
      ],
      "js": [
        "trick-play.js"
      ]
    }
  ]
}